In order to avoid readout personnel having to come into the various individual residences in order to read out consumption meters separately on location, linking the devices for consumption data detection into a network, in which these devices may communicate with one another, is practiced in the prior art. Since devices for consumption data detection of this type are typically devices having sensors, these are also referred to as sensor nodes in the framework of the network group.
Typically, in sensor networks of this type, the consumption data detected by the sensor nodes situated in the network is conducted using a relay via the individual sensor nodes to a central detection point, where the individual consumption data is collected and may then be provided for accounting. For example, readout personnel may retrieve the data at the central detection point; it is also possible if necessary to relay the centrally summarized data via long-distance data transmission.
Relaying the individual data via the different sensor nodes is known in a sensor network of this type having multiple sensor nodes, which means that a sensor node may operate both as a transmitting sensor node and also as a receiving sensor node.
In the example of the above-mentioned prior art, a sensor node may thus also represent a central collection point or may form an arbitrary sensor node of the sensor network, via which the data is relayed.
Furthermore, it is known in sensor networks of this type that multiple sensor nodes may wish to connect to a receiving node in order to relay accumulated data about consumption values or possibly also other data, such as status messages or error messages. For this purpose, a path optimization may be selected in regard to the transport path of the data by the individual sensor nodes on the basis of predefined criteria, it being possible that multiple sensor nodes wish to communicate with a specific other receiving node, since the path via this special receiving node is classified as optimal or at least preferred in relation to other paths.
Accordingly, collisions of telegrams may occur, for example, data transmissions or other transmissions which the sensor nodes wish to exchange with a receiving node, since possibly multiple sensor nodes switch to transmit simultaneously and correspondingly reception is not possible for a receiving node, since the individual telegrams or data transmissions may not be discriminated between, because they collide in time.
Moreover, sensor nodes must synchronize with another sensor node for the data exchange in order to be able to perform a data exchange following this synchronization in the scope of a predetermined exchange protocol.